1. Field of the Invention
The present invention generally relates to the fabrication of semiconductor devices. More particularly, the present invention relates compositions for removing a photoresist, methods of preparing the compositions, methods of removing a photoresist using the compositions, and methods of manufacturing a semiconductor device using the compositions.
A claim of priority under 35 U.S.C. ¶119 is made to Korean patent application no. 2005-51421, filed Jun. 15, 2005, the entirety of which is incorporated herein by reference.
2. Description of the Related Art
In the fabrication of semiconductor devices, photolithography processes are utilized in the patterning of various layers of the devices. In photolithography, a photoresist pattern is formed by selectively polymerizing portions of a photoresist layer. The resultant polymer can cause photoresist residues, organic impurities and/or etching residues generated in a later plasma etching process. The plasma etching residues may be formed on sidewalls of an underlying etched pattern and may be difficult to remove using conventional cleaning solutions.
Photoresist removal cleaning solutions typically include hydroxylamine or a fluorine compound. For example, a cleaning solution including a fluorine compound is disclosed in Japanese Laid-Open Patent Publication No. 2004-29346. This cleaning solution includes a strong nucleophilic compound, and may be effective in decomposing and dissolving a denatured polymer and plasma etching residues regardless of the types of photoresist used in the photolithography process. However, cleaning solutions of this type may not be effective in removing composites of recently introduced metals and polymers, and may corrode metal patterns.
In the meantime, a cleaning solution for removing etching residues that includes an alkanolamine compound, an organic solvent and a fluorine compound is disclosed in Japanese Laid-Open Patent Publication No. 2003-68699, and a cleaning solution for removing a photoresist that includes a fluorine compound such as tetramethylammonium fluoride, an organic solvent such as dimethylacetamide, and an additive is disclosed in Korean Laid-Open Patent Publication No. 2004-32111.
The above cleaning solutions exhibit relatively good photoresist removability and good composition stability. However, with respect to various types of metals that have been recently introduced in semiconductor manufacturing processes, the cleaning solutions may not efficiently remove fine etching residues having nanometer dimensions without damage to a metal pattern. For example, in manufacturing processes of a semiconductor device such as a dynamic random access memory (DRAM), a static random access memory (SRAM) or a flash memory device, the cleaning solutions may not completely remove fine etching residues, and may excessively etch an exposed metal layer. Thus, a product yield of the semiconductor devices may be reduced and reliability of the semiconductor devices may be deteriorated. Further, the cleaning solutions have a relatively high viscosity and a poor polymer removability, and thus the cleaning solutions do not effectively remove polymers generated in a process for forming a fine contact hole or a via hole. As a result, the polymers may remain in the contact hole, thus increasing a contact resistance of the semiconductor devices.